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Chitosan-based drug delivery systems – optimization and modelling

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Resumo:The increase of cancer incidence on the last decades and the non-existence of totally ef-ficient therapies, leads to an urgent need to develop new cures or enhance the therapies al-ready in use. Chemotherapy has been one of the most used therapies for cancer disease, and although it is very efficient in destroying malignant cells, it also comes with many disadvantages for the patients, especially due to its lack of specificity to tumour cells. In this work, all studies were made using doxorubicin (DOX), a drug commonly used in chemotherapy that apart from destroying cancer cells, also lead to future cardiotoxicity problems to the patients. A targeted drug delivery system was studied in this work, using two biopolymers, chitosan and one of its derivatives, o-HTCC, taking advantage of their pH-sensitivity. Doxorubicin was encapsulated in both chitosan and o-HTCC nanoparticles and also in superparamagnetic iron oxide nanoparticles (SPION’s) coated with both chitosan and o-HTCC. DOX release experiments were performed for different pH mediums, representing different in-vivo situations: bloodstream (7.4), tumour cells environment (6.5) and endosomal/lysosomal compartments (4.5). It was verified that an initial burst effect occurs, especially in more acidic medium, and a controlled release was then achieved. A higher drug release was observed in pH 4.5 in all nanocarriers in study. Mathematical models were applied to the data, finding that Weibull and Korsmeyer-Peppas models are the best fit in describing DOX release mechanism. It was concluded that DOX release happened through a complex and anomalous mechanism for almost all the samples, probably due to the swelling behaviour of the polymers. A study of the influence of polymer molecular weight was also performed and it was con-cluded that this parameter only has influence in nanoparticles’ size. This work indicates that these nanocarriers can be further developed for targeted drug delivery systems, especially with doxorubicin.
Autores principais:Sousa, Ana Isabel Araújo Manuel Machado de
Assunto:chitosan nanoparticles coated superparamagnetic iron oxide nanoparticles doxorubicin drug release mathematical modelling o-HTCC nanoparticles
Ano:2015
País:Portugal
Tipo de documento:dissertação de mestrado
Tipo de acesso:acesso aberto
Instituição associada:Universidade Nova de Lisboa
Idioma:inglês
Origem:Repositório Institucional da UNL
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author Sousa, Ana Isabel Araújo Manuel Machado de
author_facet Sousa, Ana Isabel Araújo Manuel Machado de
author_role author
contributor_name_str_mv Borges, João
Soares, Paula
RUN
country_str PT
creators_json_txt [{\"Person.name\":\"Sousa, Ana Isabel Araújo Manuel Machado de\"}]
datacite.contributors.contributor.contributorName.fl_str_mv Borges, João
Soares, Paula
RUN
datacite.creators.creator.creatorName.fl_str_mv Sousa, Ana Isabel Araújo Manuel Machado de
datacite.date.Accepted.fl_str_mv 2015-07-01T00:00:00Z
datacite.date.available.fl_str_mv 2018-09-07T13:54:52Z
datacite.date.embargoed.fl_str_mv 2018-09-07T13:54:52Z
datacite.rights.fl_str_mv http://purl.org/coar/access_right/c_abf2
datacite.subjects.subject.fl_str_mv chitosan nanoparticles
coated superparamagnetic iron oxide nanoparticles
doxorubicin
drug release
mathematical modelling
o-HTCC nanoparticles
datacite.titles.title.fl_str_mv Chitosan-based drug delivery systems – optimization and modelling
dc.contributor.none.fl_str_mv Borges, João
Soares, Paula
RUN
dc.creator.none.fl_str_mv Sousa, Ana Isabel Araújo Manuel Machado de
dc.date.Accepted.fl_str_mv 2015-07-01T00:00:00Z
dc.date.available.fl_str_mv 2018-09-07T13:54:52Z
dc.date.embargoed.fl_str_mv 2018-09-07T13:54:52Z
dc.format.none.fl_str_mv application/pdf
dc.identifier.none.fl_str_mv http://hdl.handle.net/10362/45950
dc.language.none.fl_str_mv eng
dc.rights.none.fl_str_mv http://purl.org/coar/access_right/c_abf2
dc.subject.none.fl_str_mv chitosan nanoparticles
coated superparamagnetic iron oxide nanoparticles
doxorubicin
drug release
mathematical modelling
o-HTCC nanoparticles
dc.title.fl_str_mv Chitosan-based drug delivery systems – optimization and modelling
dc.type.none.fl_str_mv http://purl.org/coar/resource_type/c_bdcc
description The increase of cancer incidence on the last decades and the non-existence of totally ef-ficient therapies, leads to an urgent need to develop new cures or enhance the therapies al-ready in use. Chemotherapy has been one of the most used therapies for cancer disease, and although it is very efficient in destroying malignant cells, it also comes with many disadvantages for the patients, especially due to its lack of specificity to tumour cells. In this work, all studies were made using doxorubicin (DOX), a drug commonly used in chemotherapy that apart from destroying cancer cells, also lead to future cardiotoxicity problems to the patients. A targeted drug delivery system was studied in this work, using two biopolymers, chitosan and one of its derivatives, o-HTCC, taking advantage of their pH-sensitivity. Doxorubicin was encapsulated in both chitosan and o-HTCC nanoparticles and also in superparamagnetic iron oxide nanoparticles (SPION’s) coated with both chitosan and o-HTCC. DOX release experiments were performed for different pH mediums, representing different in-vivo situations: bloodstream (7.4), tumour cells environment (6.5) and endosomal/lysosomal compartments (4.5). It was verified that an initial burst effect occurs, especially in more acidic medium, and a controlled release was then achieved. A higher drug release was observed in pH 4.5 in all nanocarriers in study. Mathematical models were applied to the data, finding that Weibull and Korsmeyer-Peppas models are the best fit in describing DOX release mechanism. It was concluded that DOX release happened through a complex and anomalous mechanism for almost all the samples, probably due to the swelling behaviour of the polymers. A study of the influence of polymer molecular weight was also performed and it was con-cluded that this parameter only has influence in nanoparticles’ size. This work indicates that these nanocarriers can be further developed for targeted drug delivery systems, especially with doxorubicin.
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instname_str Universidade Nova de Lisboa
language eng
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person_str_mv Sousa, Ana Isabel Araújo Manuel Machado de
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spelling engpt_PTThe increase of cancer incidence on the last decades and the non-existence of totally ef-ficient therapies, leads to an urgent need to develop new cures or enhance the therapies al-ready in use. Chemotherapy has been one of the most used therapies for cancer disease, and although it is very efficient in destroying malignant cells, it also comes with many disadvantages for the patients, especially due to its lack of specificity to tumour cells. In this work, all studies were made using doxorubicin (DOX), a drug commonly used in chemotherapy that apart from destroying cancer cells, also lead to future cardiotoxicity problems to the patients. A targeted drug delivery system was studied in this work, using two biopolymers, chitosan and one of its derivatives, o-HTCC, taking advantage of their pH-sensitivity. Doxorubicin was encapsulated in both chitosan and o-HTCC nanoparticles and also in superparamagnetic iron oxide nanoparticles (SPION’s) coated with both chitosan and o-HTCC. DOX release experiments were performed for different pH mediums, representing different in-vivo situations: bloodstream (7.4), tumour cells environment (6.5) and endosomal/lysosomal compartments (4.5). It was verified that an initial burst effect occurs, especially in more acidic medium, and a controlled release was then achieved. A higher drug release was observed in pH 4.5 in all nanocarriers in study. Mathematical models were applied to the data, finding that Weibull and Korsmeyer-Peppas models are the best fit in describing DOX release mechanism. It was concluded that DOX release happened through a complex and anomalous mechanism for almost all the samples, probably due to the swelling behaviour of the polymers. A study of the influence of polymer molecular weight was also performed and it was con-cluded that this parameter only has influence in nanoparticles’ size. This work indicates that these nanocarriers can be further developed for targeted drug delivery systems, especially with doxorubicin.application/pdfpt_PTChitosan-based drug delivery systems – optimization and modellingSousa, Ana Isabel Araújo Manuel Machado deBorges, JoãoSoares, PaulaHostingInstitutionOrganizationalRUNe-mailmailto:run@unl.ptrun@unl.pt2018-09-07T13:54:52Z2015-0720152015-07-01T00:00:00ZHandlehttp://hdl.handle.net/10362/45950http://purl.org/coar/access_right/c_abf2open accesschitosan nanoparticlescoated superparamagnetic iron oxide nanoparticlesdoxorubicindrug releasemathematical modellingo-HTCC nanoparticles3715523 bytesliteraturehttp://purl.org/coar/resource_type/c_bdccmaster thesishttp://purl.org/coar/access_right/c_abf2application/pdffulltexthttps://run.unl.pt/bitstreams/4bc75bb7-620d-48a9-8567-98a6361ae33d/download
spellingShingle Chitosan-based drug delivery systems – optimization and modelling
Sousa, Ana Isabel Araújo Manuel Machado de
chitosan nanoparticles
coated superparamagnetic iron oxide nanoparticles
doxorubicin
drug release
mathematical modelling
o-HTCC nanoparticles
status SINGLETON
subject.fl_str_mv chitosan nanoparticles
coated superparamagnetic iron oxide nanoparticles
doxorubicin
drug release
mathematical modelling
o-HTCC nanoparticles
title Chitosan-based drug delivery systems – optimization and modelling
title_full Chitosan-based drug delivery systems – optimization and modelling
title_fullStr Chitosan-based drug delivery systems – optimization and modelling
title_full_unstemmed Chitosan-based drug delivery systems – optimization and modelling
title_short Chitosan-based drug delivery systems – optimization and modelling
title_sort Chitosan-based drug delivery systems – optimization and modelling
topic chitosan nanoparticles
coated superparamagnetic iron oxide nanoparticles
doxorubicin
drug release
mathematical modelling
o-HTCC nanoparticles
topic_facet chitosan nanoparticles
coated superparamagnetic iron oxide nanoparticles
doxorubicin
drug release
mathematical modelling
o-HTCC nanoparticles
url http://hdl.handle.net/10362/45950
visible 1